Länge Kerstin, Gruhl Friederike J, Rapp Michael
Karlsruhe Institute of Technology (KIT), Institute for Microstructure Technology (IMT), Eggenstein-Leopoldshafen, Germany.
Methods Mol Biol. 2013;949:491-505. doi: 10.1007/978-1-62703-134-9_31.
Surface acoustic wave (SAW) devices based on horizontally polarized surface shear waves enable direct and label-free detection of proteins in real time. Signal response changes result mainly from mass increase and viscoelasticity changes on the device surface. With an appropriate sensor configuration all types of binding reactions can be detected by determining resonant frequency changes of an oscillator. To create a biosensor, SAW devices have to be coated with a sensing layer binding specifically to the analyte. Intermediate hydrogel layers used within the coating have been proven to be very suitable to easily immobilize capture molecules or ligands corresponding to the analyte. However, aside from mass increase due to analyte binding, the SAW signal response in a subsequent binding experiment strongly depends on the morphology of the sensing layer, as this may lead to different relative changes of viscoelasticity. Bearing these points in mind, we present two basic biosensor coating procedures, one with immobilized capture molecule and a second with immobilized ligand, allowing reliable SAW biosensor signal responses in subsequent binding assays.
基于水平极化表面剪切波的表面声波（SAW）器件能够实时直接且无标记地检测蛋白质。信号响应变化主要源于器件表面的质量增加和粘弹性变化。通过适当的传感器配置，所有类型的结合反应都可以通过确定振荡器的共振频率变化来检测。为了制造生物传感器，SAW器件必须涂覆一层与分析物特异性结合的传感层。已证明在涂层中使用的中间水凝胶层非常适合轻松固定与分析物对应的捕获分子或配体。然而，除了由于分析物结合导致的质量增加外，后续结合实验中的SAW信号响应在很大程度上取决于传感层的形态，因为这可能导致粘弹性的不同相对变化。考虑到这些要点，我们提出了两种基本的生物传感器涂层程序，一种是固定捕获分子，另一种是固定配体，这使得在后续结合测定中能够获得可靠的SAW生物传感器信号响应。
